Anaerobic adhesive compositions are well known in the art and have been in commercial use for several years. A basic formulation contains acrylic monomers and a peroxide source as described in U.S. Pat. Nos. 2,628,178; 2,895,950; 3,041,322; and 3,218,305.
A typical peroxide source used in the art is cumene hydroperoxide. Oligomers and polymers have also been included in anaerobic adhesive formulations and, in particular, the unsaturated acrylate moiety has been covalently linked to the oligomer or polymer as described in U.S. Pat. Nos. 3,043,820 and 3,425,988.
Other additives for such formulations include agents to confer higher viscosity such as silicone dioxide. It has also been found that for certain applications the use of an accelerator of the adhesive cure is beneficial. Known accelerators include amines, occasionally used in combination with imides as taught in U.S. Pat. Nos. 4,373,077 and 4,374,940, or resins made from the reaction of amines with aldehydes as taught in U.S. Pat. No. 3,591,438. Saccharin is also commonly added to such formulations as a component of the accelerator system.
Carboxylated cellulose esters such as those described in U.S. Pat. No. 4,590,265 are commercially available as Eastacel.RTM. resins, available from Eastman Chemical Products, Inc., Kingsport, Tenn. Such esters have been used in conjunction with acrylic monomers to make graft copolymers as taught in U.S. Pat. No. 4,605,721, bulk acrylic castings as taught in U.S. Pat. No. 4,603,160, and in conjunction with unsaturated polyesters and acrylic monomers to make formulations as taught in U.S. Pat. No. 4,539,349.
Heretofore, the use of carboxylated cellulose esters in anaerobic adhesive formulations has been unknown.